ACTIVE STEERING CURVED AND FLARED SEISMIC STREAMERS

摘要

The invention relates to seismic data acquisition in a marine environment with long streamers of hydrophone receivers towed by a boat. In a conventional acquisition program, the streamers follow straight behind the boat and when the boat has completed a pass and needs to turn to make another pass, the boat turns a very large radius turn to keep the streamers from tangling with one another. In the present invention, the streamers are steered to follow a course that is related to the navigated path of the boat. In this arrangement, the hydrophones at the far ends of the long streamers maintain a course that is related to the position of the boat as much as ten kilometers earlier even though the boat has made a significant turn. Thus, the birds that guide the streamers are arranged to counteract the pulling forces that the boat would otherwise impose on the streamers drawing the streamers off the navigated path. Using this invention, active seismic acquisition is practical even while turning and, to the extent that the boat must proceed out of the survey area, should be able to spend less time outside the survey area by making tighter turns to get back on productive seismic data acquisition.